Floating-point move to or from general-purpose register without conversion
This instruction transfers the contents of a SIMD&FP register to a general-purpose register, or the contents of a general-purpose register to a SIMD&FP register.
Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| sf | 0 | 0 | 1 | 1 | 1 | 1 | 0 | ftype | 1 | 0 | x | 1 | 1 | x | 0 | 0 | 0 | 0 | 0 | 0 | Rn | Rd | |||||||||
| S | rmode | opcode | |||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_FP) then EndOfDecode(Decode_UNDEF); if ftype == '10' && opcode<2:1>:rmode != '11 01' then EndOfDecode(Decode_UNDEF); if ftype == '11' && !IsFeatureImplemented(FEAT_FP16) then EndOfDecode(Decode_UNDEF); constant integer d = UInt(Rd); constant integer n = UInt(Rn); constant integer intsize = 32 << UInt(sf); constant integer fltsize = if ftype == '10' then 64 else (8 << UInt(ftype EOR '10')); constant integer part = UInt(rmode<0>); FPConvOp op; case opcode<2:1>:rmode of when '11 00' // FMOV if fltsize != 16 && fltsize != intsize then EndOfDecode(Decode_UNDEF); op = if opcode<0> == '1' then FPConvOp_MOV_ItoF else FPConvOp_MOV_FtoI; when '11 01' // FMOV D[1] if intsize != 64 || ftype != '10' then EndOfDecode(Decode_UNDEF); op = if opcode<0> == '1' then FPConvOp_MOV_ItoF else FPConvOp_MOV_FtoI; otherwise Unreachable();
| <Wd> |
Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field. |
| <Hn> |
Is the 16-bit name of the SIMD&FP source register, encoded in the "Rn" field. |
| <Xd> |
Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field. |
| <Hd> |
Is the 16-bit name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Wn> |
Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field. |
| <Sd> |
Is the 32-bit name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Sn> |
Is the 32-bit name of the SIMD&FP source register, encoded in the "Rn" field. |
| <Xn> |
Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field. |
| <Dd> |
Is the 64-bit name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Vd> |
Is the name of the SIMD&FP destination register, encoded in the "Rd" field. |
| <Dn> |
Is the 64-bit name of the SIMD&FP source register, encoded in the "Rn" field. |
| <Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
AArch64.CheckFPEnabled(); bits(fltsize) fltval; bits(intsize) intval; case op of when FPConvOp_MOV_FtoI fltval = Vpart[n, part, fltsize]; X[d, intsize] = ZeroExtend(fltval, intsize); when FPConvOp_MOV_ItoF intval = X[n, intsize]; Vpart[d, part, fltsize] = intval<fltsize-1:0>; otherwise Unreachable();
If FEAT_SME is implemented and the PE is in Streaming SVE mode, then any subsequent instruction which is dependent on the general-purpose register written by this instruction might be significantly delayed.
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